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Diffstat (limited to 'modules/polynomials/macros/polfact.sci')
| -rwxr-xr-x | modules/polynomials/macros/polfact.sci | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/modules/polynomials/macros/polfact.sci b/modules/polynomials/macros/polfact.sci new file mode 100755 index 000000000..225c7e852 --- /dev/null +++ b/modules/polynomials/macros/polfact.sci @@ -0,0 +1,46 @@ +// Scilab ( http://www.scilab.org/ ) - This file is part of Scilab +// Copyright (C) ????-2008 - INRIA +// +// This file must be used under the terms of the CeCILL. +// This source file is licensed as described in the file COPYING, which +// you should have received as part of this distribution. The terms +// are also available at +// http://www.cecill.info/licences/Licence_CeCILL_V2.1-en.txt + + +function [f]=polfact(p) + // Minmal factors of p + // f=polfact(p) + // + // p : polynomial + // f : vector [f0 f1 ... fn] such that p=prod(f) + // - f0 constant + // - fi polynomial + //! + // + if type(p)>2 then + error(msprintf(gettext("%s: Wrong type for input argument: Polynomial array expected.\n"),"polfact")) + end + if size(p,"*")<>1 then + error(msprintf(gettext("%s: Wrong size for input argument #%d: A polynomial expected.\n"),"polfact",1)) + end + + if norm(imag(coeff(p)))<>0 then + error(msprintf(gettext("%s: Input argument #%d must be real.\n"),"polfact",1)) + end + p=real(p) + n=degree(p);f=coeff(p,n); + if n==0 then return,end + var=varn(p); + r=roots(p);[s,k]=gsort(abs(r));r=r(k) + k=1; + while k<=n do, + if imag(r(k))<>0 then + f=[f,real(poly(r(k:k+1),var))] + k=k+2 + else + f=[f,poly(r(k),var)] + k=k+1 + end + end +endfunction |